Finding the Third Proportional to 309 and 685
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Solution
The third proportional to 309 and 685 is: 1,518.53
Step by Step Solution
- Step 1: Write the proportion equation
309 : 685 = 685 : x - Step 2: Convert to fraction form
309/685 = 685/x - Step 3: Cross multiply
309x = 685 × 685 - Step 4: Simplify right side
309x = 469,225 - Step 5: Solve for x
x = 469,225/309 - Step 6: Final answer
x = 1,518.53
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Why These Related Problems?
These problems maintain the same ratio (2.22) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.